Unbalanced shaft and method for producing same

US9080638B2 · kind B2 · utility

Assignee

• Schaeffler Technologies AG & Co. KG · DE

Inventors

• Peter Solfrank · Frensdorf, DE
• Tobias Mederer · Schwanstetten, DE

Key dates

• Filing date: Jul 7, 2011
• Grant date: Jul 14, 2015
• Expiry date: Dec 9, 2031

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T74/2121
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

An unbalanced shaft for compensating for inertial forces and/or mass moments of inertia of an internal combustion engine (1), having an unbalanced portion (8), the center of mass of which extends eccentric to the axis of rotation (11) of the unbalanced shaft (6) for generating the shaft imbalance (7), a bearing portion (9) adjacent to the unbalanced portion, and a bearing race (10) joined thereto, the outer surface (13) of which serves as a race for the rolling elements of a roller bearing rotationally supporting the unbalanced shaft, and the inner surface (12) of which retracts radially relative to the outer circumscribed circle (14) of the unbalanced portion in a bearing circumference region running in the direction of the imbalance. In order to assemble the bearing race on the bearing portion, the following geometric relationships are provided: (i) d2>d1, (ii) e>½(d2−d1), (iii) e<½(d2+d1), where d1=outer circumscribed circle diameter of the unbalanced portion and the bearing portion, d2=inner diameter of the bearing race, and e=center point offset between d2 and d1.